Nacelle structures for jet engines of an aircraft provide a housing within which the jet engine is supported. The nacelle structure typically includes a thrust reverser that can provide assistance in slowing the aircraft by redirecting the engine thrust. The thrust reverser includes a panel of the nacelle that is translated between a stowed position, for normal operation during flight, and a deployed position, for redirecting the engine thrust, such as during landing of the aircraft. The thrust reverser panel slides along a track beam to move between the stowed position and the deployed position.
Thrust reverser track beams support the thrust reverser panel during translation and join the thrust reverser panels and an engine strut or pylon for under-wing carriage of the nacelle. Other installations of jet engines may enclose the engine within a fuselage portion of the aircraft, in which case the beams join the thrust reverser panels to the aircraft fuselage.
Thrust reverser track beams have conventionally been machined from solid ingots of metal, such as aluminum. As engine diameters and bypass ratios have increased, the engine weight has increased commensurately. This has required larger and stronger beams. The increasing size of the beams requires larger aluminum ingots resulting in greater waste aluminum during manufacturing. More recently, composite track beams have been proposed, in which the generally closed-form beam is constructed from a composite material, such as graphite fiber layers impregnated with a resin material to form a graphite composite structure. Other constructions may involve a tubular hybrid beam, in which a portion of the beam is composite and a portion is metal. Although such beam constructions provide reduced weight, composite and hybrid composite beams are encumbered with difficult manufacturing techniques and poor access to critical components. Such beams can also be more difficult to inspect, due to the substantially closed construction of the composite portions of the beam.
Therefore, beams of reduced weight and improved manufacturability with ease of access are desired for use with panels of jet engine nacelle structures.